This invention relates to containers and is more particularly concerned with improvements in product containers which are in the form of a tray and which are adapted to be fabricated from paperboard or similar foldable sheet material of a character which will enable the container to be used for processing and marketing of products which may be in a flowable state when initially placed in the tray, such as, bakery products.
Tray containers have been developed heretofore which are particularly adapted for use in the bakery industry where the product may be processed in an oven and subsequently marketed without removing it from the container in which it has been processed. Products such as cakes, pastry, and the like are generally in a flowable state initially, that is, in a liquid or semi-liquid condition, and it is a requirement that the container be leakproof when filled to a predetermined level with the product and capable of withstanding oven temperatures during the baking process without damage from the heat so that the baked product may be marketed without removal from the container. For such products, containers have been developed which are adapted to be formed from thin metal foil or relatively stiff metallic sheet material which can be pressed or shaped to the desired form and become part of the final package in which the product is marketed. Such containers are generally expensive and lacking in esthetic appeal since they do not readily accept the inks commonly employed in decorative printing. Efforts have been made, with some degree of success, to provide non-metallic trays which are suitable for this purpose. One such tray structure is disclosed in U.S. Pat. No. 4,114,797 granted Sept. 19, 1978. However, there appears to be a need for trays of this type which have greater rigidity or stiffness particularly at the top margins of the sidewall panels and which are more versatile in use particularly in the bakery product industry.
It is a general object therefore of the present invention to provide an improved open top tray structure of the type described which is more versatile in use, more easily handled by the user and more economical so as to compete with trays formed of metal foil, and the like, which have been produced heretofore.
It is a more specific object of the invention to provide an improved tray structure and a method of forming the same in which the tray may be fabricated from a paperboard blank or similar foldable sheet material and may be supplied to the user as a cut and scored blank, or partially folded blank, so that it can be set up with side and end wall panels upstanding from a rectangular bottom wall panel and connected at the corners by pairs of integral web members which are folded upon each other and against the outside face of an end wall with tab members for reinforcing the corner connections which tab members extend inwardly of the opposite ends of the end walls and are heat sealed to end wall reinforcing strip members at each end, which strip members are integral with and folded downwardly of the top edge of the end wall so as to overlie the top margin of the end wall and the associated folded corner web members.
It is a further object of the invention to provide a tray structure of the type described and a method of fabricating the same so as to provide integrally hinged top edge reinforcing strip members on the sidewall and end wall panels which strip members are disposed in overlying relation on the top outside margins of the wall panels and adhesively connected to tab members forming end extensions on the sidewall reinforcing strip members so as to reinforce the top edges of the tray and the connecting corner structures.
The invention as herein disclosed and claimed comprises a tray structure and a method of forming the same from a cut and scored blank of paperboard or similar foldable sheet material which comprises a bottom wall forming panel and oppositely disposed pairs of peripherial sidewall forming panels which are integrally hinged into upstanding relation with the bottom wall forming panel and connected at the intersecting corners by pairs of integrally hinged triangular web members folded into overlying relation on the outside face of the one sidewall panel and secured by corner reinforcing tab members which are disposed beneath an edge reinforcing strip which is integrally hinged to the top edge of the associated sidewall forming panel and turned down into overlying relation on the top outside margin thereof.